Rotary position sensor

Abstract

A position sensor for sensing an angular position including at least two magnetic conductive structures, at least two magnets, a magnetic flux responsive device, and an arcuate magnet. The at least two magnetic conductive structures include a first magnetic conductive structure and a second magnetic conductive structure. The first magnetic conductive structure is substantially arcuately parallel with the second magnetic conductive structure. The at least two magnets include a first magnet and a second magnet. The first magnet being magnetically coupled with the first magnetic conductive structure and with the second magnetic conductive structure. The second magnet being magnetically coupled with both the first magnetic conductive structure and the second magnetic conductive structure. The magnetic flux responsive device is constrained to travel a path that is partially located between the first magnetic conductive structure and the second magnetic conductive structure. The path extends beyond at least one of the at least two magnets. The arcuate magnet is positioned concentrically with the path.

Description

CROSS REFERENCE TO RELATED APPLICATIONS [0001] This is a non-provisional patent application based upon U.S. Provisional Patent application Ser. No. 60 / 663,864 bearing the title “Rotational Sensor Assembly” filed on Mar. 21, 2005.BACKGROUND OF THE INVENTION [0002] 1. Field of the Invention [0003] The present invention relates to electromagnetic sensor assemblies, and, more particularly, to electromagnetic rotary position sensors. [0004] 2. Description of the Related Art [0005] Electronic devices are an increasing part of everyday life and they are presently integrated in a large number of products, including products traditionally thought of as mechanical in nature, such as automobiles. To bridge the gap between mechanical movement and electronic control, it is necessary to successfully integrate electronic and mechanical components. This gap is normally bridged by using devices such as sensors and actuators. [0006] Position sensors are used to electronically monitor the position or ...

AI Technical Summary

Benefits of technology

[0016] An advantage of the present invention is that the magnetic flux responsive device may travel beyond a portion of the device that has a varying magnetic field, thereby resulting in a static output for at least a portion of the magnetic flux sensing device's travel.

[0017] Another advantage is that the arcuate magnet provides a biasing field to a magnetic flux responsive device over a portion of its path.

[0018] Another advantage of the present invention is that the magnetic flux sensing device may travel beyond the useful sensing range and yet not be damaged by the physical movement. This advantageously allows for use of the sensor in mechanical devices, which may go beyond limits or may break and travel beyond an intended position. If such damage does occur, the sensing usefulness of the invention is not likewise destroyed and may allow continued use of the equipment in spite of the physical damage and / or at least allow the sensing system to control the device.

Problems solved by technology

A problem with this type of sensor is the physical wearing of the rotating parts, the wiping contact, and the resistive element cause a drift in the electrical signal and lead to ultimate failure of the device.

A problem with such sensors is that they depend on a movement of the magnet, and they are not able to provide information as to the static position of a mechanical component.

If the travel of the magnetic flux sensing device is not restrained in some manner, the sensing device may inappropriately come into contact with a magnet or some other structural portion of the sensor.

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